Emergency shut-off valve
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The company’s projects involve tests related to instrument control valves, and 50093-2013 stipulates that seat sealing tests must be conducted on emergency shut-off valves. Currently, the definition of the accident isolation valve is unclear: the design specifies that it refers to an automatically controlled valve that shuts down via interlock (SIS), while the supervisor believes that any FC valve must be equipped with such a function.
Shouldn’t all the valves you purchase come from the factory already having undergone pressure testing and with a test report attached?
The answer above is correct. The supervisor is right; since it’s a pressure release valve, it must be able to stay sealed. How else can sealing be ensured? Unless the valve is new and comes with a report issued by the manufacturer
Of course it’s new; national standards do not require this, but petrochemical standards do.
Stop talking nonsense; pressure tests are required before installing valves.
It seems you know a lot about this; could you please take a look at the national standards as well as Sinopec’s specifications for instrument installation to see what they say?
The valve seat sealing test should be conducted on the accident shut-off valves. For emergency shut-off valves that are normally closed and open when powered or pressurized, a valve seat sealing test is required on-site; for those that are normally open, such a testing is generally not carried out on-site. (But make sure the manufacturer has conducted tests.) The supervisor requires that the valve seat sealing test be performed properly, and strict standards are applied in operations.
Hehe, indeed they understand well – some people are used to breaking rules, so they think such regulations don’t exist.
Sealing the valve seat of the emergency shut-off valve is necessary, but the supervisor insists on conducting a pressure resistance test on the valve body; this is not required by national standards but is required by petrochemical standards. I mentioned that the specification adopted in the design notes is 50093-2013, but this did not convince the supervisor.
Strength testing is a destructive type of test; especially since some construction teams on site are not professional at all, and their attempts to carry out such tests can actually cause damage to the valves. This is particularly true for imported valves – if damage occurs, it becomes very difficult to file claims against the construction team. The procurement process alone can delay the project timeline significantly. Moreover, I’ve consulted with several manufacturers of imported valves, and they generally refuse to allow pressure testing to be carried out on site. Unless the valves are taken to their facilities or to designated testing centers, they will not provide any warranty in case problems arise later.
It depends on your skills – if you can handle the supervisor, there’s no need to do it; if not, just do it properly. You yourself said it’s been done for decades; violations are not an isolated phenomenon – whether to do it or not depends on who will bear the responsibility in the end